In recent years, silicon carbide has been employed as a material constituting a semiconductor device to achieve a high breakdown voltage and a low loss in the semiconductor device, Silicon carbide is a wide band gap semiconductor having a larger band gap as compared to silicon which has been widely used as a material constituting a conventional semiconductor device. Therefore, employing silicon carbide as a material constituting a semiconductor device can achieve a high breakdown voltage and a reduction of on-resistance in the semiconductor device. Moreover, a semiconductor device employing silicon carbide as a material also has an advantage that deterioration of the property in the use under a high-temperature environment is smaller as compared to a semiconductor device employing silicon as a material.
In the step of forming an electrode with respect to a silicon carbide semiconductor device, there is a case where one face of a silicon carbide substrate is fixed to a supporting substrate to form an electrode on the other face. For example, Japanese Patent Laying-Open No. 2012-178603 (PTD 1) discloses the steps of attaching one face of a silicon carbide substrate to a carrier substrate made of sapphire or the like, detaching the carrier substrate from the silicon substrate after grinding the other face, and forming an ohmic contact on the other face. Moreover, WO2012/035880 (PTD 2) discloses the steps of fixing one face of a silicon carbide substrate to an adhesive tape and on the other hand grinding the other face, and thereafter forming a back surface electrode on the other face.